I still do have one or two plans for Alexander though that could give him a bit of the original personality I had planned- namely dedication to friends, which I DID set into mechanics, so...
yeah, I have one or two plans.
I would imagine that the most important thing to shoot for with that would be to actually get kind of close to others in the group.
This would help a lot. When the creepy death-obsessed shaman is more talkative than you, it's kinda a bad sign 
"Bad sign? How dare you. Just because I like killing it does not mean I do not like talking."
Like some people say, you don't know your character until you really play.
What I mean is, you aren't just talking to yourself. People are responding and holding conversations with a guy who squees at death. Whereas the knight has a hard time talking to even the "good" party members. It's a little weird.
@SC: Eh, no worries. I left my backstory a little vague on purpose so it could handle retcons like that. And I did say that his father was a master-at-arms in the military, which could imply some sort of status.